Speleogenesis and Evolution of Karst Aquifers The Virtual Scientific Journal ISSN 1814-294X www.speleogenesis.info

Oсhtiná Aragonite Cave (Slovakia): morphology, mineralogy and genesis

Pavel Bosák1, Pavel Bella2, Václav Cilek1, Derek C. Ford3, Helena Hercman4, Jaroslav Kadlec1, Armstrong Osborne5 and Petr Pruner1

1 Institute of Geology, Academy of Sciences of the Czech Republic, Rozvojová 135, 165 02 Praha 6-Lysolaje, Czech Republic; E-mail: [email protected] 2 Slovak Caves Administration, Hodžova 11, 031 01 Liptovský Mikuláš, Slovak Republic; E-mail: [email protected] 3 School of Geography and Geology, McMaster University, 1280, Main Street West, Hamilton, Ontario L8S 4K1, Canada; E-mail: [email protected] 4 Institute of Geological Sciences, Polish Academy of Sciences, Twarda 51/55, 00-818 Warszawa, Poland; E-mail: [email protected] 5 Faculty of Education, A35, University of Sydney, N.S.W. 2006, Australia; E-mail: [email protected]

Re-published from: Geologica Carpathica 2002, 53 (6), 399-410

Abstract

Ochtiná Aragonite Cave is a 300 m long cryptokarstic cavity with simple linear sections linked to a geometrically irregular spongework labyrinth. The limestones, partly metasomatically altered to ankerite and siderite, occur as lenses in insoluble rocks. Oxygen-enriched meteoric water seeping along the faults caused siderite/ankerite weathering and transformation to ochres that were later removed by mechanical erosion. Corrosion was enhanced by sulphide weathering of gangue minerals and by carbon dioxide released from decomposition of siderite/ankerite. The initial phreatic speleogens, older than 780 ka, were created by dissolution in density-derived convectional cellular circulation conditions of very slow flow. Thermohaline convection cells operating in the flooded cave might also have influenced its morphology. Later vadose corrosional events have altered the original form to a large extent. Water levels have fluctuated many times during its history as the cave filled during wet periods and then slowly drained. Mn-rich loams with Ni-bearing asbolane and birnessite were formed by microbial precipitation in the ponds remaining after the floods. Allophane was produced in the acidic environment of sulphide weathering. La-Nd-phosphate and REE enriched Mn-oxide precipitated on geochemical barriers in the asbolane layers. Ochres containing about 50 wt.% of water influence the cave microclimate and the precipitation of secondary aragonite. An oldest aragonite generation is preserved as corroded relics in ceiling niches truncated by corrosional bevels. TIMS and alpha counting U series dating has yielded ages of about 500-450 and 138-121 ka, indicating that there have been several episodes of deposition, occurring during Quaternary warm periods (Elsterian 1/2, Eemian). Spiral and acicular forms representing a second generation began to be deposited in Late Glacial (14 ka – Alleröd) times. The youngest aragonite, frostwork, continues to be deposited today. Both of the younger generations have similar isotopic compositions, indicating that they originated in conditions very similar, or identical, to those found at present in the cave.

Keywords: Slovenské rudohorie Mts., Ochtiná Aragonite Cave, cave morphology, speleogenesis, mineralogy, aragonite, U-series dating

Introduction exploration. The mine workings also intersected other, smaller caves but none were so interesting or Ochtiná Aragonite Cave is unique among the significant. The cave was opened to the public in 4,250 known caves in Slovakia, although with only 1972 and in 1995 was included in the UNESCO 300 m of passages it is relatively small (Fig. 1). The World Heritage List as a component of the Caves of cave was discovered in 1954 during the excavation the Slovak and Aggtelek Karsts. of an adit (Kapusta Gallery) for iron ore P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.2

Fig. 1. Geomorphological map of the Ochtiná Aragonite Cave, showing typical cross-sections (after Bella, 1998, modified) and the sediment section in Oválna Passage with positions of the palaeomagnetic samples (black squares) and the magnetostratigraphic results (black – normal polarised magnetozone, white – reverse polarised magnetozone; for explanations see the text). Corrosion-denudation forms: Planar speleogens: 1 – horizontal solutional ceilings (Laugdecken); 2 – inclined planar walls of passages and halls descending to the floor (planes of repose, Facetten); 3 – inclined, more or less planar walls of passages and halls with smaller corrosion convex and concave forms; Concave speleogens: 4 – shallow oval irregular spoon-like depressions on roofs and walls; 5 – deeper distinct oval irregular depressions on roofs and walls; 6 – distinct, mostly horizontal niches; 7 – cupola-shaped depressions in roofs; 8 – shallow elongated channel-shaped forms in roof; 9 – horizontal elongated notches on walls; 10 – blind lateral tube-like holes; 11 – rocky windows in bedrock; 12 – narrow steep corrosion cavities developed along prominent fissures; 13 – horizontal shallow trough-like depressions; 14 – tubular karren; 15 – fissure karren on collapsed blocks; 16 – shallow drip-holes on collapsed blocks; Convex speleogens: 17 – large irregular bedrock protrusions in roofs; 18 – structurally- controlled large elongated roof bedrock juts on roofs; 19 – less pronounced elongated roof bedrock juts on roofs controlled by bedding; 20 – bedrock pendants; 21 – bedrock blades; 22 – elongate, indistinct and irregular bedrock protrusions along walls; 23 – elongated bedrock protrusions above horizontal corrosion notches; 24 – oval bedrock protrusions in floors; Structural-tectonic forms: 25 – smooth breakdown surfaces without corrosional relief; Depositional forms: 26 – sediment sequences; 27 – cones and banks of sediments at the foot of walls; 28 – planar accumulation surface; 29 – piles of collapsed blocks; Erosion forms: 30 – meandering channel on flat accumulation surface; 31 – dripholes; Other: 32 – trail (in plan); 33 – lake; 34 – planes of repose with thin cover of ochres; 35 – ochres; 36 – aragonite; 37 – stalagmite; 38 – trail (in profile).

The cave is located in the NW shoulder of Gelnica Group; Bajaník and Vozárová et al., 1983; Hrádok Hill (809 m a.s.l.) in the Revúcka vrchovina Ivanička et al., 1989). They were folded and Highlands, a part of the Slovenské rudohorie Mts., metamorphosed during the Variscan Orogeny. Rožňava District. Caves there are developed in Some of the faults and fissures were rejuvenated steeply dipping metalimestone lenses of variable during the Alpine Orogeny. Portions of the size surrounded by phyllites of the Drnava limestone have been metasomatically altered to Formation (Late Silurian to Early Devonian; ankerites and siderites by Mg and Fe-bearing

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.3 hydrothermal solutions (Mišík, 1953) ascending isolated by the phyllites, could become temporarily particular fissures (Droppa, 1957). The flooded with water. hydrothermal activity was associated with the Despite the abundance of distinctive corrosion emplacement of the Gemericum granites forms in the cave, little has been written about their (Andrusov, 1958), which have been dated to 96 Ma genesis and the hydraulic conditions under which (Kantor in Homza; Rajman and Roda, 1970). No they may have formed. Droppa (1957) mentioned younger hydrothermal activity has been recognised effects of hydrostatic pressure when the open in this region (Gaál, 1996). The cave is structurally cavities were completely flooded. Gaál and Ženiš guided, with N-S, W-E and SW-NE trends (Rajman (1986) and Gaál (1996, 1998) argued that the cave et al., 1990; Gaál, 1996; see Fig. 1). formed under phreatic conditions. Bella (1997, About 15 other caves of the Ochtiná cryptokarst 1998) was the first to recognise that the planar type have been intercepted by the Kapusta Gallery solution roofs (bevels, Laugdecken), planes of (Gaál, 1996), some of them containing aragonite repose (Facetten) and longitudinal wall notches are speleothems similar to those in Ochtiná Aragonite particularly important. Cupola-shaped depressions Cave. Other caves are found in the vicinity, as well, in the roof originated by convective processes in but they differ substantially from the Ochtiná the water. He also recognised the dominant role of cryptokarst in form (Gaál, 1998). phreatic and stagnant vadose waters in the cave´s evolution at times when the carbonate lens was Previous work water-saturated (cf. Ford and Williams, 1989, pp. 294-308). Droppa (1957) compared the tube-like cave passages to the erosion forms produced by typical Due to the difficulty of explaining the origin of flowing streams underground. Aggressive corrosion concave corrosion forms and the development of by meteoric waters percolating along tectonic passages with oval cross-sections, Choppy (1994, fissures was the main agent in the development of following ideas of Nicod, 1974), suggested that the cave. Eroded products from the chemical Ochtiná Aragonite Cave evolved as a result of weathering of the ankerites were deposited in the hydrothermal processes. Gaál (1996) contended lower parts of cave, obstructing drainage outlets that hydrothermal processes during the Upper there. Cretaceous operated at much greater depths, however, and that the accelerated Tertiary and Gaál and Ženiš (1986) argued that percolating Quaternary meteoric karst corrosion completely meteoric waters first oxidised the ankerite to create overprinted traces of any earlier hydrothermal iron hydroxides – ochres; mechanical erosion of the activity. Results of detailed geomorphological ochres then produced the larger voids. The general research do not support a hydrothermal genesis for shape of the cave thus is that of the original the surviving initial forms (Bella, 1998). Cílek et al. metasomatic ankerite bodies in the limestone, with (1998) stressed the nothephreatic origin of some of later modifications resulting from some subsequent these morphologies (cf. Jennings, 1985). No dissolution of the limestone, partly under phreatic hydrothermal minerals have been detected in the conditions. cave and the aragonite deposition was not related to In addition to the oxidation of siderite/ankerite, hydrothermal conditions (see Cílek and Šmejkal, Rajman et al. (1990, 1993) stressed the contribution 1986; Rajman et al., 1990, 1993). of other mineralisation to the development of the The presence of fresh, unweathered corrosion karst. Oxidation of the abundant gangue minerals in forms led Droppa (1957) to propose that the caves the surrounding rocks (chiefly pyrite) increased were relatively young, with speleogenesis occurring corrosional aggressivity of percolating waters by at the beginning of the Holocene. Kubíny (1959) producing H SO . Gaál (1996) also supposed that 2 4 suggested that the caves originated during limestone corrosion and ankerite oxidation and Quaternary glacials. Weathering of the ankerites mechanical washout were the main speleogenetic and successive exhumation and erosion of the agents. He considered that during periods of higher ochres began in the Tertiary and has been active rainfall the limestone lenses, hydrogeologically ever since in the view of Homza, Rajman and Roda (1970), Rajman et al. (1990). The first U series

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.4 dating of samples of the aragonite (Ford, the roof in Oválna Passage. Near the junction of unpublished, cited in Rajman et al., 1990, 1993) Ježovitá Passage and Hlboký Hall, there is also a gave two ages, one of 138-121 and the other of 14 bedrock pendant truncated by bevelling 0.4 m ka B.P. that rule out a Holocene or latest glacial below the roof level. The lowest bevels correspond origin. with the low roof level in Aragonitová záhrada near Hlboký Hall. This indicates that the retention level of stagnant water in the cave has fallen over time Morphology and/or oscillated substantially at different times. The morphology of the cave was described by Flat surfaces (smooth joint planes without any Ševčík and Kantor (1956) and Droppa (1957). It corrosional relief) produced by breakdown along consists of simple linear sections linked to a structural discontinuities (Mramorová Hall) geometrically irregular sponge-work labyrinth represent structural-tectonic forms. Depositional (Bella, 1995). forms (sediment sequences, piles of collapsed blocks, etc.) developed when clastic sediments Detailed geomorphological mapping has defined were deposited or removed from the caves: e.g., the principal and smaller morphological forms (for horizontal accumulations with desiccation cracks, location and list of forms, see Fig. 1). The forms deposited by periodic floods; alluvial cones of described hereafter are given non-genetic infiltration sediments from percolating water descriptive names owing to the fact that some them (Vstupná Hall). Small depressions (small cannot be correlated with any commonly applied meandering channels, drip-holes) resulting from the terms (e.g., those of Slabe, 1995). erosion of clayey sediments by flowing and The cave consists of two genetically different dripping water in Vstupná Hall represent clastic types of voids or principal speleogens: (1) high and erosional speleogens, which are less important in narrow linear fissures (e.g., from Vstupná Hall to the cave. Mramorová Hall; Fig. 1), and (2) a labyrinth of passages and chambers with oval cross-sections. Bedrock corrosion forms are the most abundant Mineralogy type of speleogens. Structural-tectonic forms, clastic sedimentary depositional and erosional Methodology forms are less frequent (Fig. 1). The corrosional speleogens are products of the enlargement of the Twenty three samples of ochres, clays, broken caves, occurring on the floors, walls and roofs of all aragonite speleothems and neomorphic aragonite passages and chambers. They can be classified by were collected in the cave. Twelve typical samples their geometry into: planar, concave and convex were studied by SEM and analysed on 60 points by types. The principal planar speleogens are EDAX (LINK connected to a JEOL-JXA-50A horizontal solutional ceilings (Laugdecken sensu Microprobe). A total of 34 X-ray diffraction Kempe et al., 1975 or bevels sensu Ford and analyses were made (Philips Diffractometer PW Williams, 1989) and inclined planar walls 3710). Powder produced for the X-ray work was descending to the floors of passages and halls also analysed by microprobe. Mn oxides were (planes of repose sensu Lange, 1963; Goodman, separated by sieving, and in a settling column using 1964 or Facetten sensu Kempe et al., 1975; Fig. deposition times ranging from 2 hours to 8 days. 2/3). The predominant concave speleogens are Individual portions were structurally analysed. Mn pronounced, more or less closed oval cupola- oxides, goethite and allophane were analysed by shaped depressions in roofs (Fig. 2/1). Horizontal DTA and TG (TG-750 Stanton-Reford, University concave notches extending along walls and convex of Chemical Technology, Prague). Carbon and bedrock prominences just above them indicate oxygen stable isotope ratios were measured with a positions of long-lasting paleo-water levels. In Finnigan MAT 251 Mass Spectrometer (Czech Geological Institute, Prague). Water content in addition there are elongated shallow trough-like o depressions and tubular karren produced by flowing ochres was calculated from weight loss at 70 C. water e.g., in Vstupná and Mramorová Halls. All analyses, except where otherwise mentioned, were carried out at the Institute of Geology, AS CR Corrosion bevels are developed at three different Prague. Other speleothems were visually examined levels within the cave. The highest is preserved in in the cave with a portable UV-lamp (253 and 360 Oválna Passage. Lower bevels occur in Ježovitá nm). Passage and Aragonitová záhrada and 2 m below

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.5

Fig. 2. Photographs of typical forms and speleothems in the cave. 1 – cupola-shaped depressions in the roof of Hviezdna Hall; 2 – aragonite of the oldest generation truncated by bevels in Hlboký Hall; 3 – cross-section of the passage between Ježovitá and Aragonitová Passages, showing planes of repose; 4 – the sedimentary profile in Oválna Passage; 5 – aragonite of the second generation in Oválna Passage; 6 – the youngest aragonite on ochres in Ježovitá Passage (photos 1 to 4 and 6 by P. Bella, photo 5 by A. Lucinkiewicz).

Goethite fine-grained to cryptocrystalline, although not amorphous, matrix in the ochres and as fine The ochres are soft and moist, containing 47 to acicular forms (several µm) „floating“ in fine- 56 % of water by weight. They formed from grained ochre. The moisture content of the ochres weathered ankeritic and sideritic metasomatites and distinctly influences the humidity of the air also cover cave walls as irregular crusts deposited analysed in the cave, as the ochres function as a from waters. Goethite is present as an extremely

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.6 humidity exchanger, able to adsorb and release water vapour. The ochres contain irregular laminae of birnessite, a Mn oxide. In addition to inclusions liberated by weathering (quartz), the ochres contain clay minerals (muscovite 2M1, illite, probable chlorite and 14.8 Å smectite) that were deposited on the rock surface in flooded cave conditions. Some of the ochres contain greater concentrations of P2O5 (0.3 to 1.0 %; Tab. 1).

Asbolane Fig. 3. X-ray diffraction of the asbolan layer. A – asbolan, Q – quartz, M – muscovite, G – goethite. Black Mn ochres occur as an admixture in the Fe ochres and other cave fills. They are derived from the ankeritic metasomatites, which contain about 2 Birnessite % MnO. The sequence in Oválna Passage (Fig. 2/4) Birnessite occurs as a soft black substance. It is composed of very fine-grained massive brown cannot be distinguished optically from the asbolane. clay (a mixture of goethite and clay minerals) and Birnessite was identified both in Fe ochres (as fine includes a layer about 300 mm thick that is darker coloured and irregular bands) and in the composed of several bands of Mn ochres with asbolane layers where it is probably a product of abundant intercalations of white allophane and maturation of asbolane. redeposited Fe ochres. Asbolane is abundant here Allophane as soft, black, earthy material with a clayey appearance. Complete samples and various grain- Allophane was found only in the asbolane size fractions were analysed. There were problems deposits, as separate white, fine-grained earthy of exact identification due to structural disordering, layers 30 to 80 mm thick disintegrating into cubes, or as admixtures within the asbolane. Allophane the almost amorphous nature of the mineral, and was identified by chemical analyses, X-ray from coalescing diffraction lines. Submicron-sized diffraction and particularly by DTA and TG plates of muscovite 2M1 remained in the sample analyses (Fig.4). even after extended sedimentation, masking other Allophane is an uncommon mineral in karst diffuse diffraction lines. caves (Hill and Forti, 1997, p. 179-181), but Asbolane comprise about 30 to 40 % of the black nevertheless, is relatively abundant in speleothems fills. It is usually accompanied by muscovite, and growing in abandoned mines. It has also been found also by quartz, goethite, allophane, birnessite, in pseudokarst fissure caves (Cílek, Langrová and apatite, anatase and, more rarely, by rutile and Melka, 1998). Allophane commonly forms in the authigenic La-Nd-bearing phosphate. Nickel acidic environment produced by weathering of contents can reach 1.9 to 3.9 % (Table 1), while the sulphides in the surrounding rocks. Its occurrence magnesium content is relatively stable but can be in limestone environments that are usually locally enriched (2.4 to nearly 10 %). Similar associated with high pH may therefore appear somewhat surprising. However, its presence is a variability was detected in P, Ba (0.4 to 1.4 %) and strong indication that sulphide weathering played a the rare earth elements (REE). role during speleogenesis of the cave. Sometimes the asbolane consists of microscopic globules of Mn-oxide covered by fine fossilised Halloysite organic filaments, indicating the microbial A mineral of the kaolinite group, structurally 2+ 4+ conversion of Mn to Mn . The asbolane layers similar to halloysite, occurs as an indistinct probably result from bacterial precipitation in admixture in the allophane. It was detected by X- shallow residual pools as the cave is in the late, ray diffraction. We presume that it formed either by very slow, stages of draining episodic flood waters maturation of the allophane or that the allophane (see also Andrejchuk and Klimchouk, 2001). was formed by the transformation of weathering products containing minerals of the kaolinite group.

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.7

TABLE 1 Representative chemical analyses of selected minerals Sample/Oxide ochre asbolane allophane muscovite La-Nd-bearing phosphate

SiO2 4.31 23.88 51.14 57.67 14.09

TiO2 0.05 nd 0.19 0.40 nd

Al2O3 2.48 24.24 41.16 33.45 13.71

Fe2O3/FeO* 84.01 *2.14 1.29 0.75 *5.94

Na2O 0.16 1.03 0.08 0.11 1.04

K2O 0.27 0.10 0.20 11.86 0.20 CaO 0.57 1.22 3.29 0.08 4.01 MgO 1.80 13.28 2.27 1.91 2.37 MnO 6.34 29.65 0.37 0.23 27.8 BaO nd nd nd nd 1.40 NiO 3.94 3.94 nd nd 2.87

P2O5 0.52 0.52 nd nd 5.46

La2O3 nd nd nd nd 12.21

Nd2O5 nd nd nd nd 8.91 nd - not determined

morphological comparison with samples from the Czech Karst (Cílek, 1989; Cílek and Bednářová, 1993).

Apatite Authigenic apatite forms irregular thin laminae, less than 1 mm thick, and irregular amoeba-like impregnations in the asbolane profiles. It was detected by chemical analysis and X-ray diffraction. Migration of Ca-phosphate requires an acidic environment. Phosphates, other than those derived from guano, precipitate in limestone from Fig. 4. DTA/GTA curves of asbolane (a) and allophone relatively acidic surficial P-enriched solutions, o - (b) from the Oválna Passage (velocity of heat 10 C min which have been leached from soil and weathering 1, air 10 ml.min-1, sensitivity DTA 10µV(10 mV). profiles.

Accessory minerals Anatase Muscovite 2M1 is a very common accessory Authigenic cryptocrystalline anatase forms mineral, detected in samples by X-ray diffraction, amoeba-like patches of cement in small fragments then separated and chemically analysed. The typical of brown ferruginous clayey siltstones/sandstones. chemical analysis is given in Table 1. Muscovite The fragments represent relics of kaolinitisation occurs as very fine-grained plates. It is probably products washed down into the cave. Anatase was derived from phyllites. Quartz occurs as angular detected by chemical analyses and on the basis of and corroded silt-sized grains. Its character

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.8 indicates that it was derived from dissolution of thick (Fig. 2/2). The aragonite is highly and limestones and comes from the immediate irregularly recrystallised and corroded. Fine- surroundings rather than being transported over a grained parts are still composed of aragonite long distance. Acicular rutile was found in some (radial-fibrous aggregates), with some calcite places associated with anatase cement. (blocky mosaic). Recrystallised patches consist of calcite, with some aragonite, mica and quartz (X- La-Nd-bearing phosphate ray analysis). Fine box-work structures or very fine dogtooth-like crystals cover walls of corrosion Detailed sampling of the asbolane layer revealed voids. Some voids are filled with younger milky- places with increased P content in the form of white finely radial-fibrous aggregates of aragonite apatite (X-ray identification). In other places the P or by mica-rich sediment (X-ray detection). Long content was slightly greater than Ca content. duration phosphorescence (up to 5 s.) after Nevertheless, high La (La O up to 12.21 %) and 2 3 illumination by UV-lamp differentiates the oldest Nd contents (Nd O up to 8.91 %) occurred in 2 5 generation from the younger one. Plane solution similar positions repeatedly. The La-Nd-bearing roofs (bevels) commonly truncate the oldest phases are very fine-grained (tens of µm) and aragonite. cannot be macroscopically distinguished within the black asbolane. The chemical composition of the The second generation of aragonite occurs as phosphate-asbolane layer with high REE and Ba long needles and helictites, so-called acicular and contents is listed in Table 1. spiral forms, up to several hundred millimetres long (Fig. 2/5). It displays fluorescence, but no The REE regularly occur in association with high phosphorescence in UV-light. The aragonite P concentrations. In some places the REE needles are sometimes associated with globular concentration is higher than the P contents, so the opal. Crystal faces do not display any corrosion, relationship between REE and Mn oxides has to be even under high magnification (x30 to 500). taken into account. A number of REE released by Microscope and field observations indicate that this weathering (presumably of volcanics) can migrate generation of aragonite has been growing efficiently within carbonate sequences. They form continuously up to the present time, explaining its authigenic minerals only with difficulty, but they bright white colour and fresh appearance. can be fixed in finely dispersed phosphate or in Mn oxides. Due to local permeability and diversified The youngest aragonite generation has not sources, apatite has formed only in some parts of previously been detected due to its tiny size (Fig. the karst fills. In other places the possible effect of 2/6). It occurs as fine fan-like forms with diameter phosphate molecular sieving led to formation of of 2 to 4 mm (sometimes more) and as miniature REE-bearing phosphates. The excess of the REE helictites with lengths not exceeding 40 mm. The concentration became bound to Mn oxide. helictites usually grow from centres of radial aggregates. These forms – “frostwork” – grow on Aragonite soil and Fe ochres, typically above the lake in Hlboký Hall. Here, aggregates cover thin coatings Aragonite speleothems are the outstanding of loam and ochre deposited from stagnant water. feature of this cave. According to Rajman et al. There was inhomogeneous glowing, with greenish (1990, 1993), aragonite speleothems have been and bluish points and phosphorescence of 1 to 2 traditionally classified according to their seconds duration appeared when the aragonite was morphology into: kidney-shaped, acicular and illuminated by the UV-lamp. spiral (i.e. flos ferri) forms. Cílek et al. (1998) identified three generations of aragonite Aragonite genesis speleothems according to their age and/or Two principal factors caused deposition of relationship to the speleogens. aragonite in Ochtiná Aragonite Cave: (1) high The oldest aragonite generation occurs as concentrations of Mg, Fe and Mn ions in the karst massive, whitish milky-coloured, kidney-shaped solutions, and (2) a closed and deeply-seated, partly forms and irregularly corroded relics with flooded cave environment with a high proportion of polyhedral appearance, rarely more than 300 mm the walls covered by moist Fe ochres.

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.9

The ochres act as a humidity exchanger between 1992) were adopted, the first using the older the walls and the cave atmosphere. Ochtiná standard means of estimating the ratio of the two aragonite occurs most frequently on substrates with isotopes by counting radioactive disintegrations water rising by capillary action or with very slowly (alpha particles) by scintillometry; the second using percolating water on moist sediments, which slowly the modern method of direct isotope counting in a release water vapour into the cave atmosphere. A mass spectrometer (TIMS – thermal ionisation similar situation is also observed in Zbrašovské mass spectrometry; Li et al., 1989). Aragonite Caves (Czech Republic). Mr. Štefan Roda sen. collected samples of the The isotopic ratio of carbon in the aragonite, aragonites in Oválna Passage and Hlboký Hall at δ13C, varies between -7.4 and -6.0 ‰ (PDB). 1989 or 1990 (locations on the map in Rajman et Oxygen isotopic ratio (δ18O) was found to range al., 1990). Ford dated two of them in 1990 between -7.0 and -6.3 ‰ (PDB). The C and O (90/Och1 and 90/Och2). All samples had a high isotopes thus are within the range typical for the uranium content (as is typical in aragonite) and slow, equilibrium release of CO2 from solution. The negligible amounts of detrital thorium, and thus graph in Fig. 5 compares aragonites from Ochtiná yielded precise and unambiguous ages. Results Aragonite Cave with calcites and aragonites from were partly published by Rajman et al. (1993). Starý hrad Cave (Nízke Tatry Mts., Slovakia). Ochtiná aragonites plot within the field of the lowest values of the calcite spelothems from Starý hrad Cave, but distinctly away from the Starý hrad aragonites, indicating different depositional conditions. While aragonite from the well- ventilated Starý hrad Cave shows isotopic equilibrium with common atmospheric carbon dioxide, the Ochtiná aragonite, from a closed environment, shows an anomalous isotopic composition probably caused by a different cave

CO2 composition. Rapid kinematic processes and evaporation can be excluded from any role in the deposition of the aragonite with a high degree of certainty. The genesis of the aragonite in Ochtiná Aragonite Cave cannot be completely explained until data from direct measurement of CO2 concentrations and isotopic composition in the cave air are available. Nevertheless, the isotopic data show one important result - the neomorphic aragonite of the youngest generation has an identical isotopic composition that is nearly identical to as the acicular aragonite of the second generation - both types thus were deposite under the same conditions, which are very similar to the modern ones. Fig. 5. The isotopic composition of calcite and aragonites from the well ventilated Starý hrad Cave in U series ages of the aragonite deposits the Nízke Tatry Mts. compared with the closed deeper system of Ochtiná Aragonite Cave. Very slow Samples of aragonite and calcite have been dated evaporation and isotopic equilibrium fractionation is in two laboratories – at McMaster University, proposed for the samples from Ochtiná (AII and AIII – Hamilton, Canada (Ford) and at the Institute of aragonite generations). Geological Sciences, Polish Academy of Sciences, Warsaw, Poland (Hercman). Two applications of the 230Th/234U method (Ivanovich and Harmon,

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.10

Sample 90/Och2 was a portion of aragonite yielding the remarkable U content of 15 ppm and flowstone broken during trail construction. It was an age of 13,600±500 years (one standard 20 mm in thickness, clean and opaque white, with a deviation). As a check, a second needle was coconut meat texture. For alpha dating it was cut analysed by mass spectrometry in 1995. The basal into three slices of ~7 mm thickness each (samples 15 mm of growth contained 16 ppm U and yielded Och2A, Och2B and Och2C), representing the top, an age of 13,300±68 years (two standard deviation middle and base of the deposit respectively. All error). No age could be derived for the top 15 mm three analyses yielded U contents of 8-10 ppm. (18 ppm U) because it had insufficient thorium; this Thorium was lost from Och2C during the implies that it is both very clean (no detrital extraction, with the result that no date could be contamination problems) and young, supporting the obtained. Sample Och2B from the middle third of assumption that the very tip is modern. From these the flowstone gave an age of 138,000±7,000 years measurements we establish that the needle grew BP, where ±7,000 is the one standard deviation ~52.5 mm in 13,300 years, giving a mean extension statistical counting error. Sample Och2A from the rate of about 4 mm per 1,000 years. top one third of the flowstone gave an age of Two pieces of the oldest aragonite generation 121,000±6,500 years. truncated by bevels from the junction of the Oválna If sample Och2 grew at a constant rate between Passage and Hlboký Hall (samples JOA 1 and JOA Och2B and Och2A, then the accumulation rate was 2) were corroded and partially recrystallised to ~0.41 mm/1,000 years. If it is further assumed that calcite. Measurements were done with alpha all of the deposit grew at this constant rate, then its spectrometry (OCTET PC, EG&G ORTEC; by growth commenced about 162,000 years ago and Hercman in 1999). Both analyses yielded low 230 234 ceased at approximately 115,000 years. uranium contents (0.6 and 3 ppm) and a Th/ U ratio significantly higher than 1 (about 1.4). The Sample 90/Och1 consisted of three broken high ratio, unusual in the nature, suggests that there aragonite spiral helictites (“needles” or was preferential leaching of uranium from the “whiskers”), all measuring about 60 mm in length samples during recrystallisation and/or corrosion, and tapering from ~3 mm external diameter at the rendering computed age unreliable. Therefore, base to ~2 mm at the tip. They contained central TIMS U series analyses were made by Ford in 2001 canals for water flow but the tips were sealed. The on similar eroded old aragonite and calcite needles appear to be extending by fluid permeating flowstone of the oldest generation that were found out and precipitating in the region of the tips and it as fragments within the cave. The mineralogy was was supposed that the latter were modern. The confirmed by X-ray diffraction. The extractions observed sealing of the tips might possibly be a were carried out in a clean room with laminar flow consequence of the artificial opening of the cave hoods, and two analyses were made of each sample. changing the microclimate. Results are summarised in Table 2. The basal 15 mm of one needle were analysed by the alpha method in 1990 (sample 90/Och1),

TABLE 2 TIMS U series analyses Sample No. U content [ppm] 234U/238Th 230Th/234U 230Th/232Th Age [y] 01 Och 1A 5.5 0.9934 1.046±0.003 63,000 Age cannot be aragonite calculated 01 Och 1 B 5.6 0.9975 1.057±0.003 49,000 Age cannot be aragonite calculated 01 Och 2 A 0.76 1.0268 0.9938 7,065 449,000 +69,000 calcite -42,000 01 Och 2 B 0.67 0.9999 1.0101±0.007 7,064 Age cannot be calcite calculated N.B. Error margins quoted are two standard deviations

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.11

Two analyses of aragonite show that the sample The flowstone, about 1-2 cm thick (layer No. 1 is very clean and has the high U content typical of on Fig.1) was dated by the U series alpha counting aragonite. The 230Th/234U ratio is just in secular method (Hercman). The U content (about 6 ppm) equilibrium, so that an age cannot be obtained by was similar to aragonite samples (see above). The this method. 234U/238U on the other hand is not in content of detrital Th was negligible. The analysis equilibrium, implying that the sample is certainly gave an age of 164,000±7,500 at one standard younger than 1,250,000 years. It is probably a little deviation. older than the calcite sample. Methods Two analyses of calcite are very similar. The U content is satisfactory for calcite (most Samples were demagnetised by the alternating speleothems have between 0.05 and 1.0 ppm). The field procedures up to 1,000 Oe with a Schonstedt 230 232 sample is clean ( Th/ Th >>20). In the second GSD-1 machine. The remanent magnetisation Jn analysis the 230Th/234U ratio just exceeded 1.0000, was measured on a JR-5 spinner magnetometer possibly from detritus. But it is very similar to the (Jelínek, 1966). Values of volume magnetic first analysis in all other respects. This can be taken susceptibility kn were measured on a kappa-bridge as confirmation that the age estimate of KLY-2 (Jelínek, 1973). Separation of the respective approximately 450 ka is acceptable. remanent magnetisation components was carried out by multi-component analysis (Kirschvink, Palaeomagnetism 1980). A clastic sediment section well exposed on the Results northern side of the Oválna Passage is about 0.7 m The magnetic properties, both J and k values, high (Fig. 1). From the top, it is composed of the n n of samples from layer No. 2 are distinctly different following layers: 1 – white flowstone with from those of layers Nos. 3 to 5 (Tab. 2). Sample stalagmite; 2 – clay, reddish brown, with greyish OCH 1 (layer No. 2) displays normal remanent black schlieren enriched in Mn-compounds, magnetisation. All underlying samples are massive, laminated in places, disintegrated into magnetically reversed (Fig. 1). This polarity change irregular polyhedral fragments (samples OCH 1 and can be correlated with the Brunhes/Matuyama OCH 2); 3 – alternation of reddish brown clay reversal of 780 ka B.P. (Pruner et al. 2000), because (thickness max. 1.5 cm; samples OCH 3 and OCH the speleothem date of 164 ka establishes that it 4) with layers blackened by Mn-rich minerals must be older than any of the short-lived reverse (thickness from 4 to 6 cm), and white bands with magnetic excursions within Matuyama chron (cf. allophane crystals (thickness of 1 to 5 cm; Fig. 2/4); Zhu and Tschu, Eds. 2001). 4 - clay, reddish brown, massive, disintegrates into irregular polyhedral fragments (sample OCH 5).

TABLE 3 Principal magnetic properties of samples

-6 Sample No. Jn [pT] Kn [10 SI] Polarity OCH 1 30,375 714 Normal OCH 2 35,651 1,999 Reverse OCH 3 11,879 347 Reverse OCH 4 283 176 Reverse OCH 5 1,715 161 Reverse Mean value 15,981 679 Standard deviation 16,285 771

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.12

Discussion any hydrothermal influence (cf. Curl, 1966; Cordingley, 1991; Klimchouk, 1997a). The density At several places in the cave it can be clearly of water in the phreatic zone of a karst system will seen that the voids were filled by ochres which increase as it dissolves the enclosing rock. During were later removed. Floors of passages that are continuous or periodic infiltration of “fresh” water partly filled at present have an oval shape. They into a water-saturated environment, a density were formed either before the ochres were gradient forms. This can generate convection cells produced by ankerite oxidation or before the eroded in the water body, which may produce corrosion ochre residuum was deposited in water-filled forms in the enclosing limestone. The effect is passages. essentially limited to conditions of static or very The first subsurface cavities were formed by slow water movement. In rapidly moving water this corrosion of the limestone and oxidation of the effect will be negligible. ankerite. These cavities were flooded by meteoric Convection is a differential process, the water infiltrating along the major fault line in dissolution producing roof cupola- and tube-like Vstupná and Mramorová Halls and also along the depressions in roofs that are below the waterline, lesser fissures in Hlboký Hall and Sieň mliečnej horizontal ceilings (bevels) or corrosion notches in cesty Hall. Continuous and dominantly horizontal the walls at the waterline, and inclined planar walls cavities formed along parallel fissures. Irregular beneath it. Convection circulation and solution corrosion features developed on the bedrock cannot only modify morphological forms but it can surfaces, these were considerably enlarged and also influence the entire pattern of such cave modified by later corrosional events. The only systems during their initial phases where the waters original forms still preserved are irregular niches are predominantly static or semi-static. This feature and cupolas found above the younger corrosion is particularly common where there is artesian bevels. The source of the carbon dioxide for speleogenesis (Klimchouk, 1997b). intensive corrosion can be found in the ankerite weathering with an end product of goethite, i.e. by Ochtiná Aragonite Cave is developed in an isolated lens of limestone surrounded by insoluble a process similar to that described by Kempe rocks. Such lenses readily fill with water during (1998) from Harz (Germany), according to floods and drain only slowly afterwards. Corrosion following equations: notches along the walls are produced in very acidic

2FeCO3 + 2CO2 + 2H2O = 2Fe(HCO3)2` [1] stagnant water conditions and where roofs dip down they will eventually be planed off as bevels at then the waterline. Stagnant water still forms a lake in

2Fe(HCO3)2 + 1/2O2 + H2O = 2Fe(OH)3 + 4CO2 [2] the deepest part of Hlboký Hall. The difference of elevation between the highest bevel in the cave and or the present lake level is 12 m. Nearly horizontal 4FeCO3 + O2 + H2O = 2Fe2O3.nH2O + 4CO2 [3] bedding favoured bevelling in Ježovitá Passage and Aragonitová záhrada, while corrosional ledges that where 2Fe O .nH O is limonite. 2 3 2 have developed in steeply dipping beds indicate the The frequent presence of pyrite inclusions in the corrosional origin of the bevels. Notches and bevels limestones and of allophane, a typical product of commonly intersect the older speleothems, such as acid decomposition of clay minerals, suggests that those discussed above. the corrosion might have been enhanced sulphide Planes of repose (Lange, 1963; Goodman, 1964) weathering and oxidation to H2SO4. However, the are found in many parts of the cave (Fig. 2/3). absence of any gypsum replacing limestone or of These are the inclined bedrock surfaces developed native sulphur in the cave indicates this effect was in the lower portions of cavern walls. They too probably minor. formed during periods of very slow water The origin of the niches and cupolas was linked circulation when accumulated insolubles blocked by some authors (Nicod, 1974; Choppy, 1994) with solution enlargement at the base of a wall in a flooded section of cave. In passages where bevels hydrothermal processes. However, both forms can are developed, planes of repose are similar to originate from convection induced by gravitational Facetten (sensu Kempe et al. (1975). settling of water enriched with solute ions, without

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.13

Iron ochres were formed by the weathering of only slow infiltration through narrow or choked ankerite/siderite metasomatites. The ochres are fissures, rather than direct, open communication composed principally of goethite and a variety of with flowing streams. autochthonous minerals deposited in flooded cave There are three different generations of conditions or by the dripping water. The ochres aragonite. The oldest speleothems are preserved as contain on average 50 % water. They cover a corroded relics truncated by bevels (Fig. 2/2). The substantial area of the cave and act as an important aragonite in them is partly recrystallised to calcite. humidity exchanger stabilising the microclimate. There were at least two separate periods of the Black Mn-bearing loams contain Ni-bearing growth. TIMS U series ages for recrystallised asbolane and birnessite, which developed from calcite of the older sample indicate an age of about asbolane. Mn-oxides were most probably formed 450 ka. TIMS U series ages for the aragonite by microbial precipitation at the bottom of water cannot be calculated as they are at the limit of the bodies, as recently described by Andrejchuk and method. 234U/238U on the other hand is not in Klimchouk (2001), i.e. just after the cave was equilibrium, implying that the sample is certainly drained and fresh air entered it. Beds of allophane younger than 1.25 Ma. It is probably a little older occur within the asbolane layers (Fig. 2/4). than the calcite sample and related to a warm Because it forms in a low pH environment, episode of Elster 1/2. allophane is not a common mineral in karst caves. The aragonite in the younger recrystallised We suggest that the allophane could have formed in speleothems yielded U series dates indicating an the acidic conditions produced by weathering of Eemian age (138-121 ka). The pre-recrystallisation sulphide minerals. A kaolinitic mineral similar to age may be greater. The second aragonite halloysite was formed by maturation of allophane. generation, of spiral and acicular aggregates (Fig. The asbolane layer formed an important 2/5), began to be deposited during Late Glacial geochemical barrier, which caused the (Allerod, 14 ka). Growth has continued to the concentration of the REE, the growth of La-Nd- present day. The youngest generation, of fine bearing phosphate and eventually the formation of acicular aggregates of aragonite and miniature the REE-enriched Mn oxide. helictites, is also actively growing (Fig. 2/6). Both The allogenic minerals, which have entered the of the younger generations have similar isotopic cave are extremely fine-grained and partly compositions, indicating that they originated in weathered and abraded. They indicate that the cave conditions very similar, or identical, to those found was poorly connected with the surface, allowing at present in the cave.

TABLE 4 Succession of processes during the origin of Ochtiná Aragonite Cave Age (ka) Process Water regime Notes Upper Cretaceous Hydrothermal activity Thermal Late Tertiary Initial speleogenesis Phreatic Pleistocene Cave enlargement Epiphreatic, vadose >780 Corrosion, bevels and Highstand Asbolane as a product of deposition of sediments sulphide weathering by oxidising <780 (Oválna Passage) Lowstand waters Glacial? Erosion/redepositon of cave Fluctuations Periods of water highstands not fill, possible bevels excluded, CO2 released from ankerite decomposition in oxidising waters 500 Speleothems, the oldest Lowstand Calcite recrystallised from generation I aragonite prevails and is 450 somewhat younger than aragonite (ca 50 ka)

Glacial? Corrosion, bevels, cut of rocky Highstand and CO2 released from ankerite pendants, erosion/redeposition fluctuations decomposition in oxidising of cave fill waters

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.14

Conclusions Dating this sequence of processes is a complicated and risky task. We can assert that the The modern morphology of the cave reflects a cave started to form before 0.78 Ma according to comparatively complex evolution under particular the palaeomagnetic data from the oldest dated cave lithological and hydrogeological conditions within fill in Oválna Passage. The roof of that passage is an isolated lens of karst rock surrounded by the highest preserved bevel to have developed insoluble rocks. Such lenses can become filled with under the succeeding vadose conditions. We may water, often with artesian confinement. Primary tentatively link the formation of this highest bevel phreatic subsurface cavities were formed by the with the oldest sedimentary fill. Therefore, vadose corrosion of the limestone and oxidation/erosion of conditions probably were established 0.78 Ma. The the ankerite. Elongated, chiefly horizontal cavities phreatic phase of cave development has to be older formed along parallel fissures. Irregular corrosion (Late Tertiary/Pleistocene), but it cannot be dated forms developed on the bedrock surfaces. The properly. It appears that the age of cave origin is niches and cupolas are relics of phreatic speleogens close to that suggested by Kubíny (1959) and created by convection induced by gravitational, Homza, Rajman and Roda (1970). The sequence of density-derived circulation of water in a regime of cave development summarised in Table 4 is based very slow flow. Hydrothermal effects are not primarily on the U series dating of flowstones and necessary. The abundant pyrite together with a aragonite/calcite speleothems. common allophane indicates the carbonic acid corrosion was most probably enhanced by sulphide weathering producing diluted brines. Thermohaline Acknowledgements convection cells operating in the flooded cave The authors wish to express their thanks might also have influenced the wall morphology. especially to Dipl.-Ing. Jozef Hlaváč, Director of Younger corrosional events under vadose the Slovak Caves Administration in Liptovský conditions changed the original forms to a large Mikuláš and Mr. Ján Ujházy, Head of the Ochtiná extent. The intensity of corrosion was enhanced by Aragonite Cave for permission to conduct research carbon dioxide from ankerite weathering in the and to take samples during a period of 1996 to oxidising meteoric waters. The water-level 2001. We acknowledge the contribution of: Dr. fluctuations were repeated several times as Karel Melka and Mr. Jiří Dobrovolný (X-ray indicated by several levels of flat roofs (bevels), analyses and interpretations), Dipl-Ing. Anna wall niches and planes of repose. Bevels form by Langrová (microprobe analyses; all from corrosion in stagnant water conditions. Roof Laboratory of Physical Methods, Institute of planation was influenced both by limestone Geology, AS CR Prague), Dr. Daniela Venhodová bedding and by the duration and intensity of water (production and evaluation of palaeomagnetic data; convection. Bevels intersected older speleothems. Department of Palaeomagnetism, Insitute of Corrosion notches along the walls indicate that the Geology AS CR Prague), Dr. Karel Žák (isotopic levels of stagnant water were stable for long analyses; Czech Geological Institute, Branch periods, representing significant phases of cave Barrandov, Prague), and Dr. Jana Ederová (DTA- enlargement. Planes of repose also indicate slow GTA analyses, University of Chemical Technology, water circulation following floods; accumulated Prague). The research was carried out under the insolubles blocked solution enlargement at the base Agreement on Scientific Co-operation between the of a cave wall. Slovak Caves Administration and the Institute of Water-level oscillations and water flow have to Geology AS CR. Costs were covered from sources be very slow, as indicated by the fact that the of the Caves Administration (Task B. of the Main sediment section studied in Oválna Passage Activity Plan in 1998), Plan of Scientific Activity survived several submergences. Nevertheless, the No. Z 03-013-912 of the Institute of Geology AS velocity of flow during the early phases of the cave CR, and Grant No. A3013201 of the Grant Agency evolution had to be sufficient to transport the clastic of AS CS. U series analyses by Ford at McMaster products of the ankerite disintegration into lower University were supported by a grant in aid of levels of the cave. research from the National Scientific and Engineering Research Council of Canada.

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.15

References Droppa A. 1957. Ochtiná Aragonite Cave. Geografický časopis 9, 3: 169-184. Bratislava Andrejchuk V.N. and Klimchouk A.B. 2001. (in Slovak, Russ. and Germ. summ.). Geomicrobiology and Redox Geochemistry of the Karstified Miocene Gypsum Aquifer, Ford D. C. and Williams P. W. 1989. Karst Western Ukraine: The Study from Zolushka Geomorphology and Hydrology. Unwin Hyman, Cave. Geomicrobiology Journal 18: 275-295. 601 pp. London-Boston-Sydney-Wellington. Andrusov D. 1958. The geology of Czechoslovak Gaál Ľ. 1996. Exploration and protection of Carpathians, Part I. Publ. House Slovak Acad. aragonite caves in surroundings of the Hrádok Sci., 304 pp. Bratislava (in Slovak). Hill. In Sprístupnené jaskyne – výskum, ochrana a využívanie jaskýň, zborník referátov, P. Bella Bajaník Š. and Vozárová A. (Eds.). 1983. (Ed.): 130-133. Liptovský Mikuláš (in Slovak, Explanations to the geological map of the Engl. summ.). Slovenské rudohorie Mts. – eastern part (in Slovak). Geol. Inst. D. Štúr, 223 pp. Bratislava Gaál Ľ. 1998. Karst phenomena in the surroundings (in Slovak). of the Hrádok Hill and their relation to the Ochtiná Aragonite Cave. In Výskum, využívanie Bella P. 1995. Principles and theoreticaly-metodical a ochrana jaskýň, zborník referátov, P. Bella aspects of classification of cave morphological (Ed.): 44-52. Liptovský Mikuláš (in Slovak, types. Slovenský kras 33: 3-15. Liptovský Engl. summ.). Mikuláš (in Slovak, Engl. summ). Gaál Ľ. and Ženiš P. 1986. Karst of the Revúcka Bella P. 1997. The views to the genesis of the Highland. Slovenský kras 24: 27-60. Liptovský Ochtiná Aragonite Cave (in Slovak). Aragonit 2: Mikuláš (in Slovak, Russ. summ.). 13-14. Liptovský Mikuláš (in Slovak). Goodman L. R. 1964. Planes of repose in Höllern, Bella P. 1998. Morphological and genetic features Germany. Cave Notes 6, 3: 17-19. Castro of the Ochtiná Aragonite Cave. Aragonit 3: 3-7. Valley. Liptovský Mikuláš (in Slovak, Engl. summ). Ivanička J., Snopko L, Smopková P. and Vozárová Choppy J. 1994. La première karstification. A. 1989. Gelnica Group – Lower Unit of Synthèse spéléologique et karstique. Les Spiško-gemerské rudohorie Mts. (Early facteurs géographiques 3. Spéléo-Club de Paris, Paleozoic, West Carpathians). Geol. Zbor. Geol. Club Alpin Français, 1-70. Paris. Carpath. 40, 4: 483-501. Bratislava. Cílek V. and Bednářová J. 1993. Silcretes in the Hill C. and Forti P. 1997. Cave Minerals of the Bohemian Karst. Český kras (Beroun) 18: 4-13 World. Second edition. Natl. Speleol. Soc., 463 (in Czech, Engl. summ.). pp. Huntsville. Cílek V., Bosák P., Melka K., Žák K., Langrová A. Homza Š., Rajman L. and Roda Š. 1970. Origin and and Osborne A. 1998. Mineralogical evolution of karst phenomenon of the Ochtiná investigations in the Ochtiná Aragonite Cave. Aragonite Cave. Slovenský kras 8: 21-68. Aragonit 3: 7-12. Liptovský Mikuláš (in Czech, Liptovský Mikuláš (in Slovak, Engl. abs., Germ. Engl. summ.). summ.). Cílek V., Langrová A. and Melka K. 1998. Ivanovich M. and Harmon R.S. 1992. Uranium Pseudokarst phosphate-allophane speleothems Series Disequilibrium. Applications to from ice caves of the Podyjí National Park. Environmental Problems. 2nd Ed. Clarendon, Speleo (Praha) 26: 20-27 (in Czech, Engl. 910 pp. Oxford summ.). Jelínek V. 1966. A high sensitivity spinner Cílek V. and Šmejkal V. 1986. The origin of magnetometer. Studia geophysica et geodetica aragonite in caves. The study of stable isotopes. 10: 58-78. Praha. Československý kras 37: 7-13. Praha (in Czech, Engl. summ.). Jelínek V. 1973. Precision A.C. bridge set for measuring magnetic susceptibility and its Cordingley N. J. 1991. Water stratification in active anisotropy. Studia geophysica et geodetica 17: phreatic passages. Cave Science 18(3): 159. 36-48. Praha. London. Jennings J.N. 1985. Karst Geomorphology. Oxford, Curl R. L. 1966. Cave conduit enlargement by Basil Blackwell, 293 pp. natural convention. Cave Notes 8, 1: 4-8. Castro Valley. Kempe S. 1998. Siderite weathering, a rare source of CO2 for cave genesis: the Eisenstein Stollen

P.Bosák et al. / Speleogenesis and Evolution of Karst Aquifers, 2005, 3 (2), p.16

System and adjacent caves in the Iberg, Harz Nicod J. 1974. Les régions karstiques de Slovaquie Mountains, Germany (abs.). Journal Cave Karst et de Hongrie septentrionale. Bull. Soc. Géogr., Studies 60, 3: 188. Huntsville. N.S. 82, 12, 14: 11-25. Marseille. Kempe S., Brandt A., Seeger M. and Vladi F. 1975. Pruner P., Bosák P., Kadlec J., Venhodová, D. and „Facetten“ and „Laugdecken“, the typical Bella, P. 2000. Paleomagnetic research of morphological elements of caves developed in sedimentary fill of selected Slovak caves. In standing water. Annales de Spéleologie 30, 4: Výskum využívanie a ochrana jaskýň, zborník 705-708. Moulis. referátov z 2. vedeckej konferencie, P. Bella Kirschvink J. L. 1980. The least-squares line and (Ed.): 13-25. Liptovský Mikuláš (in Czech, plane and the analysis of palaeomagnetic data. Engl. Summ.). Geophysical Journal of the Royal Astronomical Rajman L., Roda Š. jr., Roda Š. sen. and Ščuka J. Society 62: 699-718. Oxford. 1990. Physico-chemical investigation of the Klimchouk A. 1997a. Artesian speleogenetic karst phenomenon of the Ochtiná Aragonite setting. Proc. 12th Int. Congr. Speleology 1: 157- Cave. Final Report. MS, Slov. Muz. Ochr. Prír. a 160. La Chaux-de-Fonds. Jaskiniarstva archive: 1-46. Liptovský Mikuláš (in Slovak) Klimchouk A. 1997b. Speleogenetic effects of water density differences. Proc. 12th Int. Congr. Rajman L., Roda Š. jr., Roda Š. sen. and Ščuka J. Speleology 1: 161-164. La Chaux-de-Fonds. 1993. Untersuchungen über die Genese der Aragonithöhle von Ochtiná (Slowakei). Die Kubíny D. 1959: Aragonite cave in Slovakia. Höhle 44, 1: 1-8. Wien. Ochrana prírody 14, 1: 17-18. Bratislava (in Slovak). Slabe T. 1995. Cave Rocky Relief and its Speleogenetical Significance. Zbirka ZRC 10, Lange A. 1962. Water level planes in caves. Cave 128 pp. Ljubljana. Notes 4, 2: 12-16. Castro Valley. Ševčík R. and Kantor J. 1956. Aragonite cave in the Lange A. 1963. Planes of repose in caves. Cave Hrádok Hill near Jelšava. Geologické práce, Notes 5, 6: 41-48. Castro Valley Zprávy 7: 161-170. Bratislava (in Slovak). Li W.-X., Lundberg J., Dickin A.P., Ford D.C., Tásler R. (Ed.) 1991. Owen 90-New Zealand. Schwarcz H.P., McNutt R. and Williams D. Czech Speleol. Soc., 60 pp. Trutnov. 1989. High-precision mass-spectrometric uranium-series dating of cave deposits and Tásler R. and Cílek V. 1999. Decoration of giant implications for paleoclimatic studies. Nature domes in the Bohemia Cave, New Zealand: the 339: 534-536. World biggest aragonite cave? Speleofórum ´99 18: 35-40. Praha (in Czech, Engl. abs.). Mišík M. 1953. Geology of the area between Jelšava and Štítnik. Geologický sborník Slov. Zhu R.X., Tschu K.K. (Eds.) 2001. Studies in Akad. Vied 4, 3-4: 557-587. Bratislava (in Paleomagnetism and Reversals of Geomagnetic Slovak). Field in China. Beijing, Sciences Press, 168 pp.